During the last year of this project, we have observed that: limited but not extensive Kaposi's sarcoma responds well to lymphoblastoid interferon with an overall response rate of 67% CR plus PR. The symptoms and signs of ARC/AIDS respond to azimexon therapy as do the abnormal immune parameters. Such responses were seen in ARC patients but were not seen in those with AIDS. A trial of isoprinosine was found to show no benefit and no modification of immune parameters in either ARC or AIDS. Current trials include lymphoblastoid interferon plus velban in Kaposi's sarcoma, IL-2, and copovithane (BAYi7433) in ARC. In the laboratory, we have observed that ARC/AIDS patients have impaired, in vitro immune responses to HSV-1, HSV-2, and CMV. Interferon production, blastogenic responses, and NK cells responses to the viruses are all impaired. In addition, IL-2 can correct the NK and blastogenic responses of the patients at least in part. During evaluation of surface markers on cultured, mitogen-stimulated cells, we discovered that expression of the IL-2 receptor (Tac) was markedly depressed, even after 5 days of stimulation with mitogens such as PHA. Nucleic acid metabolism of AIDS patients' lymphocytes was studied. Several nucleic acid metabolizing enzymes such as adenosine deaminase and purine nucleotide phosphorylase were found to be markedly immune deficient. B-cell and macrophage function are now under study. In a clinical immunological study of the first 135 patients entered into our program (20% symptom-free, 60% ARC, and 20% AIDS), it was found that immune deficiency was present in all three groups but was most severe in patients with AIDS. (SR)